Am 2024-03-21 11:13, schrieb Hal Murray via time-nuts:

...

In feb 2018 the European net was late some minutes because it was
unclear
who had to pay / provide power + blind power compensation for some
Balcanese
enclaves / exclaves. Easy to check at home with Stanford SR-620 +
Lucent GPS receiver + 9V AC wall wart + attenuator as DUT.

<
https://www.flickr.com/photos/137684711@N07/38870750440/in/datetaken/

They managed to sort that out.

For uwave frequency setting it is useless in my opinion. Just imagine
the
phase noise multiplying up from 50/60 Hz to 10 GHz or so. It would be
a mole hill in X-band.

cheers,  Gerhard

I believe the local electric generation utilities have largely divested
themselves of maintaining an accurate 60 Hz mains frequency, both
instantaneously and total cycles per day.

I know that my home clocks that count cycles from the power lines no
longer show accurate time. In fact, compared to GPS time, I often see
more than 5 seconds error in just a week's time, here in Southern
California.

If I don't reset those power-line (no crystal reference) clocks, I've
surely seen errors of 30 seconds accumulate. That holds true for
stand-alone power-line clocks and the clocks in microwave ovens and
kitchen appliances. But, all those clocks in appliances roll the minute
digit about simultaneously, when the time had been set accurately to the
second. This indicates the various appliance clocks are counting cycles
accurately, but the cycle count per day varies and is not well maintained.

All those appliances loose the time setting when there is a power
failure. It is probably mild OCD, but I try to set all those clocks
using a GPS clock and to the second. I used to rely on a mains-frequency
clock for A/V timing but now I use a GPS Clock by Nick Sayer, sold on
Tindie; it displays time to tenth-second. This GPS time is closely
tracked by my Heathkit WWV (not WWVB) Most Accurate Clock; a few days
after carefully setting a mains frequency appliance clock, the time is
very typically seconds off GPS time.

-Best wishes,

Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)

On 3/21/2024 3:13 AM, Hal Murray via time-nuts wrote:

When I worked in the oil and gas industry our plant control room had 2 clocks; one ran on mains AC the other was a fairly accurate quartz clock that looked identical. The were quite often out during the working day but the night shift operator tried to have the AC clock accurate in the hour before day shift start. Trying to get the workforce to work on time.

-----Original Message-----
From: Peter Reilley via time-nuts time-nuts@lists.febo.com
Sent: Saturday, March 23, 2024 10:53 AM
To: Hal Murray via time-nuts time-nuts@lists.febo.com
Cc: Peter Reilley preilley_454@comcast.net
Subject: [time-nuts] Re: Power line timing -- setting a clock

Back in the 1970's I installed Westinghouse power plants in the US and around the world.  On the control panel there was a sort of clock that showed the difference between the AC produced by the plant and some reference, could be WWV or a crystal, I don't remember.

The "clock" had only one pointer and would advance clockwise if the plant was running fast and it would move counter-clockwise if the plant was running slow.  If the pointer went around more than one turn then you did not really know where you were.

In the US the clocks were not used because the frequency was determined by the regional dispatcher.

Overseas the clocks were ignored by the operators because no one used AC driven clocks.  People were just happy to have power and did not care about the frequency.  If the voltage was reasonably close the the frequency was more or less correct that was much better than the alternative, no power.

On 3/21/2024 6:13 AM, Hal Murray via time-nuts wrote:

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If you want to geek a bit more: here is the European view on things. You’ve seen the 2018 incident come along, this guy talks mostly about his own observations and the rules pertaining to them.

https://wwwhome.ewi.utwente.nl/~ptdeboer/misc/mains.html

—

Ruben van der Leij

There are a few things to consider here.   First is that California is
part of the western grid.
The western grid is certainly not out by more than a few seconds at most
at any particular
time but it will always make up the slippage to restore the correct
time.   Clocks on the
grid will be correct on average.   There are web sites that track this.

Your particular case:
1)   At times a section of the grid may break away from the western grid
because of equipment
failure.   During this time the local grid will be working to restore
the local grid stability.
They wont worry about maintaining the correct time.   Eventually they
will reconnect to
the western grid.   You may not notice this.

2)   Your local circuit will have circuit breakers at substations. A
fault on your local circuit,
like a tree branch touching the line, will cause the breaker to open.  
Many breakers have
an auto-close feature.   After a certain time, generally just a few 60
Hz cycles, they will
re-close automatically.   They will repeat this a certain number of
times and then remain
open.   You may notice this as the lights flickering.   During this time
you will loose
a few cycles.   A non auto-close breaker will stay open until an
operator manually closes
it.

There are probably a few other scenarios where a section of the grid may
loose correct
time keeping but the main grid will always strive to be correct on average.

On 3/22/2024 9:52 PM, Larry McDavid via time-nuts wrote:

On Sun 2024-03-24T10:42:13-0400 Peter Reilley via time-nuts hath writ:

In much of the western grid this is no longer the case.  Once the
power company ran ads touting how auto reclosers made the power more
reliable to protect its customers from darkness.  Now the power
company runs ads touting how this does not happen to protect its
customers from wildfires.  We are not supposed to notice this shift.

--
Steve Allen                    sla@ucolick.org              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
1156 High Street              Voice: +1 831 459 3046        Lng -122.06015
Santa Cruz, CA 95064          https://www.ucolick.org/~sla/  Hgt +250 m

What is described here is an independent system not a local utility
connected
to a larger grid.
As part of a large grid, imagine that you are an operator at a power plant.
Your generator is capable of X watts.   The total capacity of the grid may
be 10,000X watts.   If you open the throttle of the generator fully then
you
can output X watts and the grid will have 10,001X watts total.   If you
bring your plant to idle you will put out 0 watts.

In either case your effect on the grid is extremely small but not
zero.   The only
way to change the frequency of the grid is if the central dispatcher orders
enough of the grid capacity to increase or decrease their output. In
this way
the grid frequency and phase can be brought back to align all the clocks to
the correct time.

On 3/24/2024 7:20 AM, Rsec Van der leij via time-nuts wrote:

I don't immediately find the reference now, but my recollection is that
there was relaxation in the requirement to maintain accurate mains
frequency a few years ago. About that time, I began to notice my
mains-synched digital clocks began to not keep accurate time.

All I can tell you with good confidence is that my home digital clocks
that are synched to the mains no longer keep accurate time here where I
live in Anaheim. And, I am very confident all those appliance clocks
still roll the displayed minute simultaneously when I have set them
accurately as I usually do. I am confident these clocks are counting
cycles correctly. I watch time carefully as TimeNuts do!

However, Anaheim may be an unusual or perhaps a special case as the City
of Anaheim is my electric utility provider. The city owns the power line
distribution system, buys power at a wholesale level and sells it
directly to city residents. Our electric utility does not follow the
rules or pricing structure our nearby public electric utility does. For
example, Anaheim has only a the usual baseline price per kWh and then
one--and only one--rate change after that for residential users. The
public electric utility stair-steps the rate at least four times.

Further, Anaheim owns, and operates within the city, seven large natural
gas-fired turbine peaking generators; these fill at least a 4 city
blocks square area. My electric energy cost is always a bit lower than
that of surrounding cities.

Does that have any relevance to this time-keeping by mains frequency
issue? I have no idea. When I want accurate time, I use my GPS clocks.
But, it is annoying to always see my appliance and desk clocks display a
time different than by GPS. Truly, I have seen these mains-synched
clocks as much as 20 seconds off GPS time; on a short-term basis, the
displayed time might be slow (the usual case) or fast.

Anaheim owns part of the Four Corners power generation system and used
to own part of the San Onofre nuclear station (now being disassembled).
I believe much of the major intertie network is actually dc, so
frequency is not a consideration in that case.

Both my Heathkit WWV GC-1000 (in HI SPEC) clocks and my Geppetto GPS
clocks display time to tenth-seconds. I have one set of these clocks
side-by-side and the seconds digits roll together within less than a
tenth-second by slow motion video.

"Youse guys" can quote regs about maintaining mains for clock accuracy,
but it is not working here. Anaheim is the largest city in Orange
County, California, with a population of some 340,000+. Remember
Disneyland? Yep, here in Anaheim.

Best wishes,

Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)

On 3/24/2024 7:42 AM, Peter Reilley via time-nuts wrote:

...